Resistor



A. E. COBB June 9, 1959 RESISTOR Original Filed Jan. 18, 1955 FIG. 3

INVENTOR ALFRED E 6055 BY I ATTORNEY United States Patent RESISTORAlfred E. Cobb, Lexington Park, Md.

Original application January 18, 1955, Serial No. 482,688, now PatentNo. 2,847,543, dated August 12, 1958. Divided and this application June26, 1957, Serial No. 668,265

3 Claims. (Cl. 338--76) (Granted under Title 35, US. Code (1952), see.266) The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes without the payment of any royalties thereon or therefor.

The present invention relates to a resistor and more particularly to aresistor which is variable.

A novel resistor is provided which is an integral part of an electricalapparatus, e.g. a card switch and thus the requirement for externalresistors is obviated in some circuits and lessened in number in allcircuits. Resistance material is painted on a piece of spring plasticmaterial and is inserted on the underside of the spring contact bed andby construction and position is made to touch a whole row of springloaded contacts in a circuit. Thus, a variable resistor is (formed sincea varying amount of resistance can be tapped oil. by a varying selectionof spring loaded contacts.

This application is a division of application Serial No. 482,688, nowPatent No. 2,847,543, issued August 12, 1958, filed January 78, 1955,for Card Switch System.

An object of the present invention is the provision of a resistorelement for an electrical apparatus for producing a variable resistor.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings wherein:

Fig. 1 illustrates an isometric view of a resistor which is adapted tobe used in an apparatus.

Fig. 2 is an isometric rear and side view of an apparatus including theresistor shown in Fig. 1.

Fig. 3 shows a vertical section of the apparatus of Fig. 2.

Referring now to the drawing, wherein like reference charactersdesignate like or corresponding parts throughout the several views thereis shown in Fig. 1 a resistor 51 having a main body portion 52 and teeth53 which are formed from one sheet of springy insulating material, suchas a non-conducting plastic. Two insulated strips of resistance material54 are painted on main body portion 52 and a conducting paint coating 55is provided for teeth 53.

In Fig. 2 resistor 51 is shown situated among the undersides of springloaded contacts 15 which extend through a support 14 comprising sheet38, opening 41, and sheet 37. It may be desired to employ the resistoras a potentiometer in which case the end contact would probably requiregrounding by a connection to clip 44. Only the pressure obtained by thespring action of the resistor 51 provides contact between rods 42 andteeth 53.

In Fig. 3, wires 61, 62 and 63 are shown connected to clips 44 on thecontact rods numbered 64, 65, and 66. Rods 64 and are shown extendedthrough holes 18 in an insulating sheet 17 to join conducting bar 13.Resistors 51 connect the various rods 15. To obtain a variableresistance, connections are required to the pins 36 which are connectedto wires 61 and 62. The resistance path extends from wires 61 throughrod 65 to bar 13, along bar 13 to contact 64, from contact 64 throughresistors 51 to wire 62. It is obvious that the resistance can be variedby merely changing the contact 64 that joins bar 13. If it is desired tohave a potentiometer, the voltage supply is placed between wires 62 and63 through suitable pins 36 mounted on a support 35 and wire 61 then hasthe variable voltage output. It is thus seen that an unskilled operatorcan obtain a variable resistance or potentiometer by the insertion ofthe disclosed novel resistor in an electrical apparatus.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. In a bed containing a plurality of parallel rows of spring-loadedinsulated single contacts; a resistor comprising a flexible insulated,springy material insert having a rectangular-shaped main body withappendanges extending from the long sides of said main body, saidresistor adapted by its springiness to be in pressure contactrelationship with said spring loaded contacts, resistance materialpainted on the appendages and in two insulated strips adjacent to theappendages, and conducting paint superimposed on the resistance materialon the appendages.

2. In a bed containing a plurality of parallel rows of spring-loadedinsulated single contacts; a resistor com prising a flexible insulated,springy material insert having a body portion and side portions, saidresistor adapted by its springiness to be in pressure contactrelationship with said spring loaded contacts, resistance material onsaid side portions and in two insulated strips on said body portion, andconducting material on said side portions and in contact with saidresistance material.

3. In a bed containing a plurality of parallel rows of spring-loadedinsulated single contacts; a resistor comprising a flexible insulated,springy material insert having a body portion and fingers extendingtherefrom, said resistor adapted by its springiness to be in pressurecontact relationship with said spring loaded contacts, resistancematerial on said fingers and in two insulated strips on said bodyportion, and conducting material on said side fingers and in contactwith said resistance material.

References Cited in the file of this patent FOREIGN PATENTS 665,053Great Britain Jan. 16, 1952

